1. Field of the Invention
This invention relates to a vehicular headlamp and, more particularly, to a structure of a shade of the headlamp. A vehicular headlamp, generally, is so constituted that a reflector and lens of the headlamp control distribution of light emitted from a bulb thereof to obtain a predetermined light distribution pattern. In recent years, a headlamp has also been developed in which light distribution control is performed solely by a reflector without relying on any lens to create a predetermined light distribution pattern.
2. Description of Related Art
In such a headlamp, if emitted forward from the lamp, light proceeding upward may give glare to drivers of oncoming vehicles and pedestrians. It is therefore essential to obtain a light distribution pattern in which upwardly directed light is suppressed as much as possible when an auxiliary lamp is turned on. Many conventional headlamps have adopted structures in which a shade is attached to a reflector to cut direct light rays emitted from the headlamp forward from a bulb.
The shade is subject to high temperatures due to heat from the bulb. Also, the shade is generally made of a metal, and formed in an integrated body by a drawing process or a bending process. However, with the headlamp having such a shade, the following problems arise. That is, as described above, in a recent headlamp, since the reflector thereof distributes light rays where the lens thereof tends to be formed as plain glass or in a condition close to it, the shade is readily visible from the outside of the headlamp. Therefore, it is necessary to provide the shade with ornamental qualities as well as shielding function.
Though the shade needs to be formed with a shade body for cutting the direct light and an attachment leg member for securing the shade to a reflector, it would be difficult to obtain a shade in a desired shape because a crack may occur when molded if the shade shape is complicated where the shade body and the attachment leg member are formed by a drawing process. Accordingly, when an attempt is made to provide ornaments or a decorated surface of a three-dimensional pattern, a shade body would hardly be formed due to restrictions imposed from workability of press molding.
In contrast, if the shade is formed by a bending process, restrictions likewise in the case of the drawing process would be less in terms of molding. However, shade shapes formable by such a bending process themselves are limited from the outset, and therefore, it is more difficult to obtain a shade worth admiring than in the case of the drawing process.